Indicator light tower



FIG. 1 is a perspective view of an indicator light tower, showing my new design;

FIG. 2 is a front view thereof.

FIG. 3 is a side view thereof.

FIG. 4 is a top view thereof; and,

FIG. 5 is bottom view thereof.

In FIGS. 1-5, the broken lines defining structural elements depict environmental subject matter that forms no part of the claimed design. 

The ornamental design for an indicator light tower, as shown and described. 